1.secluded a．隐居的(living in seclusion)：隐蔽的(screened or hidden from view)
词根记忆：来自seclude(v.隔离)
例：New houses built in secluded rural areas are relatively free of air pollutants．//a secluded life隐居生活
2.secrete v.藏匿(to hide)：【生】分泌（to form and give off）
词根记忆：se+crete(生长，增长)--分泌
例：The human body secretes more pain-blocking hormones late at night than during the day.
派生词：secretion(n.分泌：分泌物)
3.secretion n．分泌(the process by which liquid substances are produced by parts of the body or plants)；分泌物(a product of secretion formed by an animal or plant)
词根记忆：来自secrete(v.分泌)
例：The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins.
4.secular a.世俗的，尘世的(worldly rather than spiritual)
联想记忆：sec(跟随)+ular--跟随的；随大流的--世俗的
例：As an educator ,a builder of institutions and organizations, and a major figure in the Black Church and secular feminist movements, Nannie Helen Burroughs was one of the best-known and most well-respected African Americans of the early twentieth century.
派生词：secularism(n.世俗主义；现世主义)
5.secure v.获得（to obtain, to acquire）；a．安全的(safe)
例：I secured the services of a good lawyer.
6.sedentary a．久坐的：需长坐的(doing or requiring much sitting)
词根记忆：sed(坐)+ent+ary--久坐的
例：Coronary patients who exercise most actively have half or less than half the chance of dying of a heart attack as those who are sedentary.
7.sediment n.【地】沉淀物(material deposited by water, wind or glaciers)
词根记忆：sedi(坐)+ment--坐下去的东西--沉淀物
例：These sediments are composed of calcium carbonate shells of marine organisms.
派生词：sedimentary(a．沉积的；沉淀性的)；sedimentation(n．沉积；沉淀)
8.sedimentary a.沉积的；沉淀性的( of, relating to, or containing sediment)
词根记忆：来自sediment(n.沉积)
例：The higher the ratio of oxygen 18 to oxygen 16 in a sedimentary specimen, the more land ice there was when the sediment was laid down.
同根词：sediment(n．沉积，沉淀物)
9.seedling n.幼苗；树苗(sapling)
词根记忆：seed(种子)+ling(小)--幼苗
例：seedlings of Douglas fir花旗松的幼苗